That is quite true Kirsty. My girlfriend and I probably said it a little before we were really in love, but we thought we were at the time. I can now say that I truly am in love with her. I care more about her own happiness than my own, but this is stipulated by the fact that she cares the same for me so I know I am not just sacrificing my own happiness. If something were to happen to her (i.e. an accident of some sort) and I lost her, I would be able to move on eventually but would always have a part of me attached to her.

Just make sure youre careful about things, and careful about unbalancing things as people have mentioned above